1. Field of the Invention
The present invention relates to a technique for a zoom lens barrel that changes imaging magnification by moving in the direction of the optical axis thereof between a retracted position and an image-taking position.
2. Description of the Related Art
Among image pickup apparatuses such as digital cameras including zoom lens barrels, an apparatus proposed by Japanese Patent Laid-Open No. 2009-122640 includes, so as to reduce the size thereof, a catoptric element such as a prism that guides incoming light received through a plurality of lens groups to an image pickup device by refracting the incoming light in a direction intersecting the incoming optical axis, which is a first optical axis.
In the above proposal, the light entering through a first lens group provided in the lens barrel is refracted toward the image pickup device in the direction of a second optical axis that is substantially orthogonal to the first optical axis by using the prism or the like provided to the rear of the first lens group.
In the apparatus proposed by Japanese Patent Laid-Open No. 2009-122640, however, motors and so forth are necessary that drive optical members provided on the first and second optical axes during a zooming operation. In such a case, if zooming and focusing operations are simultaneously performed while a movie is being taken, the quality of recording sound may be deteriorated. This is because noise from a plurality of drive units may also be recorded.